The present invention relates to crystallizable polyolefin polymers, and more particularly to linear low density polyethylene and copolymers of ethylene with alpha-olefins having 3 to 8 carbons containing a novel nucleating composition, whereupon cooling from a molten state, the temperature of crystallization and rate of crystallization are significantly increased.
The use of nucleating agents to modify the crystalline structure of thermoplastic high polymers and to increase the temperature of crystallization and rate of crystallization is well known in the art and is discussed in detail, for example, in U.S. Pat. No. 3,367,926 to John F. Voeks, the disclosure of which is incorporated herein by reference in its entirety. The above-described polymer composition, while in the heat-plastified state, can be fabricated into various articles, such as fibers, filaments, films, tubes or the like, by extrusion or molded by compression or injection or otherwise into molded articles and then cooled to "set up" the shape and induce crystallization. By increasing the temperature of crystallization and rate of crystallization, the cycle time can be reduced and production rates increased.